The invention concerns a sealing means and sealing valve for container openings consisting of a housing with a gas release connector, in which a sealing element is arranged the element exhibiting a circumferential sealing bead which seats, in an unpressurized state, on a sealing surface and in a pressurized state is separated from the sealing surface.
An element of this kind has become known through the German utility model G 85 34 913.5.
Storage batteries, for example require a gas-release valve which safely prevents the escape of battery acid and H.sub.2 gas under normal pressure conditions and, at a predefined overpressure within the battery cell, opens to facilitate a gas-release. It is simultaneously necessary to guarantee that no fluid ,e.g., air unintentionally flows from the outside into the cells of the storage battery. Storage batteries, in particular lead batteries for motorized vehicles, are articles of mass-production and these gas-release valves and sealing means must therefore be produced in as economical a fashion as possible.
The known sealing means according to G 85 34 913.5 exhibits, as sealing means, a disc-shaped seal with a conical seal projection. The disc-shaped seal is connected with a spring which, for its part, is supported in the housing. The spring presses the conical seal projection of the seal against a valve seating. In the event of over pressure inside a container which is to be sealed, the seal is lifted against the force of the spring so that the fluid can escape. In this known sealing means the positioning of the seal is effected largely by means of the conical seal projection and the valve seating. This has the consequence that when the sealing means is opened the positioning is lifted-off. The seal is then guided in a sideward fashion only by means of the spring and the inner wall of a housing. The known sealing means is subjected to pressure only in the vicinity of the opening pressure at the valve seating.
A further sealing valve according to German patent publication P 41 35 711.6 exhibits a lid portion upon which a wall portion is formed. On the wall portion a ring-bead is provided for which runs circumferentially around the cylinder-shaped stopper. The sealing bead facilitates a compensation of tolerance fluctuations in the inner diameter of the wall portion occuring during mass-production of the sealing valve and assures that the sealing bead always seats, in a sealing fashion, on the outer wall of the gas-release connector. The known sealing valve seats only in a linear fashion on the wall of the gas-release connector and in this manner undesireble adhesive forces between the inner side of the wall portion and the outer wall of the gas-release connector are prevented.
It is the underlying purpose of the invention to further improve a valve of the known kind and to provide for a sensitive pressure response for the valve which can be adjusted to the smallest pressure fluctuation in vessels which are to be sealed.